Blog Archives

In the morning the Pymatuning wetland students continued learning about wetland hydrology, particularly how different wetland types are defined by differences in hydrology, including differences in hydroperiod, water source, and hydrodynamics. We also discussed how ecosystem processes like decomposition, primary production, and nutrient cycling are affected by differences in hydrology. Things then got a bit peaty, with a discussion of some of the unique features of peatland hydrology.

The students learned how to setup and launch data-logging pressure transducers, and suspended these in PVC surface wells in preparation for our fieldwork in the afternoon. We also setup four camera traps and brainstormed a bit about how we wanted to position them to assess differences in animal activity within a few microhabitats in a marsh. They clearly want to “capture” a muskrat (Ondatra zibethicus).

Installing a well in Pymatuning Creek Marsh.

Pressing Onoclea sensibilis.

We spent most of the afternoon at Pymatuning Creek Marsh in Ohio. It was a sunny and warm day in the field, although the deer flies were particularly abundant and thirsty. We all donated a little energy to the ecosystem, but it was well worth it for the opportunity to add so many plants to our “must-know” list. The marsh was very dry this year, and walking through it was much easier than in years past; however, a few students did manage to find the holes in the muck. We installed wells in areas characterized by different vegetation, including an area with abundant spatterdock and standing water, and an area dominated by willow shrubs. The students also mounted camera traps in different microhabitats, and began their plant collections. We returned to the lab to press plants.

Today began a three-week, field-intensive course in wetland ecology at Pymatuning Laboratory of Ecology. It is my fourth year teaching this course and it is still a highlight of my year. This year’s class seems to be a really great and engaged group of upperclass undergraduates, with a range of expertise spanning environmental geology, environmental biology, ecology and evolution, and biochemistry. I look forward to getting to know them all over the next few weeks.

Soils collected along a gradient from a wetland to an upland. Can you place them in the correct order along this gradient?

Substantial rain over the past few days occurred here in the Pymatuning region, with lots of localized flooding. Today was also unusually cold for this time of year. So we got off to a wet and cold start, but it didn’t slow us down. Needless to say, both the wetlands and the uplands on our tour of local sites this morning were quite wet! Wetland “hydrology” was everywhere! We discussed the definition of a wetland and how to identify them. The unusually wet conditions highlighted the need to look at more than just the present hydrology, and to examine the longer-term indicators of wetland conditions: the vegetation and soils. We also observed aerenchyma tissue in the stem and rhizome of spatterdock, discussed the likely composition of gas bubbles rising out of a marsh soil, speculated on the causes of tree mortality in a recently flooded area, and examined wetland and upland soil characteristics. And of course we identified a few plants…most importantly poison ivy. As I mentioned to the students, poison ivy will not be on the “must-know” plant list for the exams, but their identification skills will instead be tested in more “real-world” ways.

In the classroom we had an overview of wetland definitions, wetland types, and the ecosystem services that wetlands provide humanity. Later in the afternoon, the students utilized the FWS wetland mapper to examine the classification and description of the wetlands we visited earlier in the day.

The Pymatuning wetlanders spent the morning learning more about wetland hydrology, and the afternoon installing wells and collecting data on plant communities at Pymatuning Marsh. They equipped the wells with pressure transducers, which log total pressure and temperature every 15 minutes. We will leave them in the marsh for the next week or so, and then examine the data to assess the causes of diurnal water-level fluctuations.

The students also established two transects along the water-depth gradient in the marsh and collected percent cover estimates for plant species, as well as measurements of water chemistry and and water depth. We will collect similar datasets from other sites over the next few days as part of a project comparing the vegetation of different wetland types. As the students were collecting data on plant communities they also began their plant collections.

For many of the students, this was their first experience walking through a deep marsh with an organic-rich substrate. As the video below shows, it took them some time to find their bog legs. Another fun day at PLE!

The Pymatuning wetlanders preparing to enter the marsh to install surface wells and collect data on plant communities.

Installing a well at Pymatuning Marsh.

Estimating percent cover of plant species.

Jessica, the class TA, examining an amphipod.

Sparganium eurycarpum (burweed)

What is this growing on the midrib of a Peltandra virginica (Arrow-arum) leaf?